3 sentences

1. 这双鞋是用真牛皮做的。

   zhè shuāng xié shì yòng zhēn niú​pí zuò de.

   These shoes are made of genuine cowhide.

   Source: Dong Chinese Dictionary

2. 他总爱吹牛皮，没几句话是真的。

   tā zǒng ài chuī niú​pí, méi jǐ jù huà shì zhēn​de.

   He always likes to brag; hardly anything he says is true.

   Source: Dong Chinese Dictionary

3. 这种纸很牛皮，怎么撕都撕不烂。

   zhè zhǒng zhǐ hěn niú​pí, zěn​me sī dōu sī bù làn.

   This paper is very tough; it won't tear no matter how you pull it.

   Source: Dong Chinese Dictionary